U.S. Pat. No. 3,260,726 (1966) discloses various heterocyclic thioureas with aryl substituents on the imido nitrogen of the thiourea moiety, which are disclosed as herbicides. Example 4 of said patent shows the preparation of (N,N-dimethyl-N'-phenyl)carbamimidothioic acid (3-methyl-2-quinoxalinyl)ester.
Wolf et al. discloses the preparation of unsubstituted S-2-quinoxalyl-isothiouronium chloride [carbamimidothioic acid (2-quinoxalinyl)ester, hydrochloride] in J. Am. Chem. Soc., 76, 2266 (1954). This compound was prepared by Wolf et al. as an intermediate in the preparation of quinoxaline-2-thiol.
The quinoxaline esters of carbamimidothioic acid of the present invention, on the other hand, are variously substituted with alkyl substituents on one or both nitrogens of the thiourea moiety, or with nitro, alkyl or carbalkoxy substituents on the quinoxaline ring, or with a combination of such substitutions. Additionally, the compound of the present invention exhibit the pharmacological properties of preventing gastric ulcers, reducing gastric secretions, and lowering blood pressure.